Resize images to fit them evenly into 1 rectangle image

I will provide you high quality illustrations that you will need to fit inside 1 rectangle 1880 x 984 pixels image. They need to fill in the whole 1880 x 984 rectangle.

You can see here an image that is done WRONG, the pictures need to be re-aligned and re-sized to create horizontal rectangle.

Here is another example which is aligned evenly:
This is what I need, but still wrong dimension of overall rectangle, has to be 1880 x 984.

This resizing task will need to be completed 16 times (for 16 rectangle images made from different number of illustrations).

$10 total for full work. Negotiable.